Impulse: A fire hose is turned on the door of a burning building in order to knock the door down. This requires a force of 1000 N. If the hose delivers 40 kg of water per second, what is the minimum velocity of the stream needed to knock down the door, assuming the water doesn't bounce back?

A. 15 m/s
B. 20 m/s
C. 25 m/s
D. 30 m/s


Answer: C

Physics & Space Science

You might also like to view...

A(n) ____________________ is a circle whose center moves in a circular orbit around the Earth

Fill in the blank(s) with correct word

Physics & Space Science

The densest, coldest clouds are called _____________

a. reflection nebula b. dark nebula c. Bok globules d. molecular clouds

Physics & Space Science

When I was a teenager, I saw a Candid Camera sequence in which they filmed a person struggling with a suitcase that (unknown to that person) contained a large and rapidly spinning gyroscope. Imagine you are carrying such a suitcase where the gyroscope’s angular velocity is oriented horizontally to your right as you carry it in your right hand. Imagine you try to make a left turn, thus turning the suitcase to the left around a vertical axis. What does the suitcase do?

A. It turns to the left as one would expect. B. It tries to turn instead to the right. C. It tries to rotate around a horizontal axis, with its right face turning upward. D. It tries to rotate around a horizontal axis, with its left face turning upward. E. It tries to rotate around a rightward axis, with its front edge moving up.

Physics & Space Science

The coefficient of volume expansion of olive oil is 0.68 × 10-3 K-1. A 1.00-L glass beaker is filled to the brim with olive oil at room temperature. The beaker is placed on a range and the temperature of the oil and beaker increases by 25 C°

As a result, 0.0167 L of olive oil spill over the top of the beaker. What is the coefficient of linear expansion of the glass? A) 1.0 × 10-6 K-1 B) 2.0 × 10-5 K-1 C) 4.0 × 10-6 K-1 D) 3.0 × 10-5 K-1 E) 1.0 × 10-5 K-1

Physics & Space Science